1. Field of the Invention
The present invention relates to a semiconductor integrated circuit device, and more particularly relates to a semiconductor integrated circuit device on which a chip operation test can be easily carried out on a bare chip.
2. Description of the Related Art
In general, a bare chip, that is, a semiconductor chip that has been cut out from a wafer, is permanently packaged with a plastic or ceramic film and subjected to a screening test that is an initial inspection test through which defective articles are screened out. Only articles that have passed the test, that is, only articles, with assured quality, are shipped. However, a multi-chip-module (referred to as "MCM" hereinafter) has entered the market recently, and the demand has expanded rapidly. In accordance with the expansion of the demand, it is desired to assure quality of bare semiconductor chips.
In this case, MCM is an assembling technique by which the delay of a signal transmission between packages can be avoided when a plurality of semiconductor chips of ICs or LSIs are directly provided on a highly dense wiring board, so that the characteristics of the chips can be fully utilized. Therefore, MCM is a promising technique superior to the prior art, in which the manufacturing characteristics of silicon are better utilized, and system performance can be enhanced.
The conventional test on a semiconductor chip is carried out in the following manner: A probe for inspection use is contacted with the electrode terminal of a semiconductor chip. Alternatively, the test can be made after the semiconductor chip has been assembled into a semiconductor package.
In this connection, as described above, in the case of an MCM in which a plurality of semiconductor chips is provided on one base board, the yield of the MCM is directly affected by the quality of each chip. Therefore, it is required to carry out the quality assurance test under the condition of a semiconductor chip, and a quality check test is performed using a socket used exclusively for the semiconductor chip, wherein this socket is temporarily used only for the test. However, the size of the electrode terminal and the interval between the electrode terminals of the semiconductor chip are very minute. Therefore, it is difficult to accurately match the terminal size and interval of the exclusive socket to those of the semiconductor chip. Therefore, the cost of developing the exclusive socket is increased.
When the screening test is performed on a semiconductor chip, the semiconductor chip tends to be damaged by external factors such as static electricity when it is conveyed or packaged. For this reason, the reliability of quality assurance deteriorates.